How to Keep the Particles at Low Temperature

The engineering seems to be concentrating on how to insure that the particles remain coherent together, they don't decohere. The common way of attempting to do this appears to be keeping the particles at low temperature. To get the temperature down really low are well, they use liquid helium, as one would expect. But an interesting part about this story is that id helium itself isn't cold enough for what they need to do. And so they need a special ice touph ttay. Now, where do they get the liquie helium three from? One of the sponsors was the american army.